/ Dave Pawson <dpaw...@nildram.co.uk> was heard to say:
| Agree with Norm about exercisesection being quite a mouthful,
| Either his generic section,

I don't think <section> is available for this use. The sectioning elements
(sect1..5, section, refsect1..3, refsection) form a well-defined hierarchy.

While it would be technically possible to reuse them outside that context,
I think it would be a bad idea. It would, for example, be impossible to limit
the content model of exercise sections independently of the content model
of chapter sections.